More Details on "Patrice T"

The unnamed metal detector user facing a court case on illegal artefact hunting comes from the east of France and had "deep archaeological knowledge" (AFP 'Priceless' haul of over 27,000 artefacts seized in France', 16/12/2020). - 11:32

French authorities have seized a "priceless" haul of over 27,000 archaeological artefacts ranging from Bronze Age bracelets to Roman coins that had been secretly amassed by a single person in the east of the country, customs said Wednesday. The seizure of the 27,400 objects was the result of a year-long investigation conducted by French customs, Belgian authorities and the French culture ministry. The hoarder, who has not been named and now faces a criminal probe, had built up the collection for personal and trading purposes, the French customs service said. He had amassed the collection himself using metal detectors as well as what appears to be a deep archaeological knowledge. The man had first aroused suspicion in 2019 when he told authorities he had found almost 15,000 Roman coins by chance on land he had acquired in Belgium. The French customs service then confirmed that this haul had actually been built up through "the looting of various sites in France", it said. The case has now been handed to the judiciary, with the man risking a colossal fine and possibly jail time.

Where is meant? Champagne-Ardenne, Franche-Compte, Alsace, or Lorraine maybe? What comprises "deep archaeological knowledge" in the contexct of finding things? When they allege that Mr T had "built up the collection for personal and trading purposes", did the French customs service actually catch him selling stuff, or is that just a surmise based on a stereotype?

UPDATE 18th Dec 2020
Despite some innaccuracies, Hannah Thompson ('French customs seizes 27,000 looted archaeological artefacts', the Connection 17 December 2020) seems to have more details:

French customs confirmed on Wednesday December 16 that it had seized more than 27,000 pieces of objects classified as “cultural goods”, hidden at the property of a collector from Lorraine. The pieces are “priceless” and of “exceptional quality”, the ministry for culture said. They include bracelets and torches from the Bronze Age and the Iron Age; a rare Gallo-Roman mosaic; thousands of coins from the Roman Gaul era; and belt buckles from the Merovingian era, the medieval age, and the Renaissance. All of the pieces appear to have been illegally dug up from sites across the east of France. The case dates back to October 18, 2019. A Frenchman who had recently bought a piece of land in Belgium told authorities that he had found a treasure trove of Gallo-Roman coins when digging on his new land. [...] The discovery made the authorities suspicious [...] It is thought he was trying to sell many of the objects in Belgium.